Sling attachment device



FIG. 1 is a perspective view thereof;

FIG. 2 is a top view thereof;

FIG. 3 is a bottom view thereof;

FIG. 4 is a front view thereof, the back view being a mirror image thereof;

FIG. 5 is a left side view thereof; and,

FIG. 6 is a right side view thereof.

The broken lines immediately adjacent the shaded areas represent the bounds of the claimed design while all other broken lines are directed to environment and are for illustrative purposes only; the broken lines form no part of the claimed design. 

CLAIM The ornamental design for a sling attachment device, as shown and described. 